Marion Le Gall, PhD
Nutritional Ecology of Herbivorous Pests
For as long as I can recall, I have loved insects. What began as childhood curiosity eventually became a scientific pursuit. My research now focuses on how nutrition shapes insect physiology, behavior, and performance, and how these insights can be leveraged to better understand insect ecology and improve sustainable pest management strategies.
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To study insect nutrition, I use a physiological framework known as the Geometric Framework for Nutrition (GFN), which examines how organisms balance multiple nutrients to meet their physiological needs. This approach provides a powerful lens for understanding how nutritional trade-offs influence development, reproduction, behavior, and population dynamics across insect systems.
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A central theme of my work is applying nutritional ecology to integrated pest management (IPM). In some contexts, I investigate how nutritional constraints can be exploited in the field to reduce pest performance. In others, such as insect mass-rearing for the Sterile Insect Technique (SIT), my goal is the opposite: to optimize diets that improve insect quality, fitness, and overall program success. Ultimately, this work aims to reduce reliance on insecticides in agricultural systems.
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In my role as Supervisory Entomologist at M3 Agriculture Technologies, I also work on the development and implementation of X-ray–based sterilization technologies as alternatives to traditional gamma irradiation.
By integrating insect nutrition, physiological-ecology, and radiation biology, my research aims to improve the effectiveness and sustainability of pest management programs.
Research Interests
In the Geometric Framework for Nutrition, nutrients that an herbivore eats are modeled in a geometric space. This method yields a visual and quantitative representation of how variation in nutrients affects food preference. An animal's performance can also be mapped onto a geometric space to determine how nutrients impact variables like growth, reproduction, dispersal, etc. This framework was developed in the lab with laboratory colonies, however for my research, I also apply it in the field with wild insect populations. Thanks to this integrative approach, I have been able to better understand the basic nutritional biology of economically damaging pest species and help farmers find solutions to herbivorous pest problems in West Africa, Australia, and the United States.
Publications
Brosemann, J. K., Overson, R., Cease, A. J., Millerwise, S. C., & Le Gall, M. Nutrient supply and accessibility in plants: effect of protein and carbohydrates on Australian plague locust (Chortoicetes terminifera) preference and performance. Frontiers in Insect Science, 3, 1110518.
Le Gall, M., Touré, M., Lecoq, M., Marescot, L., Cease, A., & Maiga, I. (2023). Senegalese grasshopper—a major pest of the Sahel. In Biological and Environmental Hazards, Risks, and Disasters (pp. 77-96). Elsevier.
Le Gall, M., Boucher, M., & Tooker, J. F. (2022). Planted-green cover crops in maize/soybean rotations confer stronger bottom-up than top-down control of slugs. Agriculture, Ecosystems & Environment, 334, 107980.